摘要:

AbstractA method is described for the determination of the binder content of bituminous mixtures, rapid enough for plant control and sufficiently accurate for routine analysis. The soluble binder is extracted from the mixture with methylene chloride; from an aliquot portion of the solution the solvent is removed by distillation under reduced pressure, and the binder weighed. The time required for the estimation of binder content varies from 30 to 90 minutes, according to the type of mix. Analysis of over one hundred representative bituminous road materials has shown excellent agreement with figures obtained by British standard methods. A brief review of standard methods is given with the times required for analysis.

ISSN:0368-4075    

DOI:10.1002/jctb.5000650101

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractOn irradiation of rubber sols with ultra‐violet light in the absence of oxygen, gelation takes place under certain conditions. The nature of thin reaction was studied by following its progress by means of viscosity measurements. Reaction curved determined for rubber sols in carbon tetrachloride, in the absence of accelerators, were found to be fundamentally, of the same type as those obtained in their presence. They differed, however, in showing a slight initial decrease in viscosity owing 10 degradation, probably due to traces of oxygen. The mechanism of the reaction and the possible structures of the reaction feature are discusse

ISSN:0368-4075    

DOI:10.1002/jctb.5000650102

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractThe mixed fatty acids are first separated into sovorul groups by crystallisation from appropriate solvents at low temperatures. In each group the proportions of linolenic, linoleic, oleiu and saturated acids are determined spectrographically after isomerisation with alkali,1Palmitic acid and other saturated acids may be determined by fractional distillation of the completely hydrogenated methyl eaters of the total mixed fatty acids, or from direct ester‐fractionation of the methyl esters of each group of the mixed acids obtained by low temperature crystallization. The accuracy of the determination depends largely on the degree to which, by low temperature crystallisations, the mixed fatty acids are resolved into (i) portions rich in olcic and/or saturated acids (with only minor amounts of linoleic and linolenic acid) and (ii) portions rich in linoleic and/or linolenic acid (with relatively small proportions of oleic and saturated acids). The procedure is illustrated by determination of the component acids of linseed oil, of wheat germ oil, and of two specimens of rubber seed oil.The propects of rubber seed oil as a drying oil for the paint industry are briefly discusse

ISSN:0368-4075    

DOI:10.1002/jctb.5000650103

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractComponent acid analyses have been carried out on body And liver oils from the Cape John Dory (Z. capensisC. and V.) in fat or thin condition. In both liver and body, increase in fat content of the fish results in an increase in the content of the highly unsaturated C20, C22and C,14acids in the oil, and a decrease in the degree of average unsaturation of the C18and C26acids. In the liver the latter effect is dominant and therefore the iodine value of the liver oil tends to decrease with increase in fat content of fish: in the body, however, the former effect prevails and increase in iodine value of the body oil results.As in other species with a diffuse system of fat storage, the liver oil in distinguished from the body oil by its higher content of C18unsaturated acids, and by a decreased content of the more highly unsaturated C20and C23acids. The distinction between the liver and body oils is not as marked as is usual in such species, however, and this is related to the comparatively high degree of fat storage in the liver of the John Dory.

ISSN:0368-4075    

DOI:10.1002/jctb.5000650104

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractThe use of pure benzole as a raw material for the manafacture of plastics has demanded the production of a grade containing very low quantities of sulphur as thiophen. Recent experience has shown that, in order to estimate this thiophen, which may be present in quantities of the order of 0·001% wt. sulphur as thiophen, reliance has been placed almost entirely on the well‐known isatin test, although many variations of the test are being used and comparable results are not being obtained. The present work was undertaken to enable a reliable test to be suggested that is capable of standardisation in the manner of other tests commonly used for testing tar and its produc

ISSN:0368-4075    

DOI:10.1002/jctb.5000650105

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractIt is a matter of common knowledge that borax (Na2B4O7) is a very efficient agent for retarding the set of plaster of Paris. Its effect on the setting time is shown by the typical curve given in Fig. 1 (after Gibson and John‐on1). One of the explanations offered2for this retardation phenomenon is that borax is physically adsorbed on the surface of the crystal, thus reducing the rates of solution of the hemihydrate and the formation of gypsum nuclei. Thin short investigation was initialed to test and the validity of this postulatio

ISSN:0368-4075    

DOI:10.1002/jctb.5000650106

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractB‐Chloroacridine (II) was converted to acridine in 80% yiold by hydrogenation in the presence of potassium hydroxide and ranoy‐nicked catalyst at atmospheric picture followed by oxidation of the resulting acridnn (III) with chromic acid. The scope of the now reaction for the preparation of substituted acridities is discussed, with examples. A critical comparison is made of the various methods available for the preparation of acrid

ISSN:0368-4075    

DOI:10.1002/jctb.5000650107

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY

摘要:

AbstractBefore 1939 the only practical method of converting sea water into drinking water Was by distillation. This method, whilst subjected to improvement during the war, could not be applied for use in the rubber dinghies in which stranded aircrews must exist until they are picked up. For the reason an alternative method was essential and a chemical means of removing the dissolved salts from sea water was developed which was simple in operation and which provided a largo margin of dunking water over that which could be carried in tilts in the emergency packs.This article describes the development of the process and the results finally achieved. Furthermore, it shows how the properties of ion exchange materials, which in peacetime hud been used mainly for softening hard waters, could be applied to other purposes und assist in the solution of an otherwise difficult chemical problem.

ISSN:0368-4075    

DOI:10.1002/jctb.5000650108

出版商:John Wiley&Sons, Ltd    

年代:1946

数据来源: WILEY